In order for a personal computer manufacturer to be competitive in its rapidly changing industry, it must have the ability to introduce new and varied products to the market very quickly. One of the hindrances computer manufacturers experience in producing and delivering new and varied computers is the time required to design and manufacture a chassis to house the new electronic components demanded by consumers. Even using the most advanced CAD tools, designing, tooling and producing a computer chassis is a task that typically requires several months from start to finish. Accordingly, it is necessary that a single chassis of a particular design be able to accommodate a broad range of electronics.
One of the challenges in designing a chassis to accommodate a broad range of electronics is the need for connections to external devices such as storage devices, video, keyboard, mouse, serial interfaces, parallel interfaces, speakers, networks cards, etc. The reason allowing for external connections is such a challenge is that current computer systems are designed with a principal circuit carrying board, often known as a "system planar" or "motherboard" secured within a chassis with external connectors secured directly to the system planar and with corresponding openings provided in the chassis to allow a cabled connection to be made with the external device.
The number, type and shape of connectors and external devices is constantly changing and expanding, and consumers demand a broad variation in the number and type of external connections available on each computer system. Because the placement of each external connector requires a corresponding access opening in the computer chassis, either the system planar must be designed to conform to the access openings in an existing chassis, which can limit the variation in connector options, or the chassis design must follow the system planar design, extending the time in which the system can be delivered.
An additional problem faced by system planar designers is that expansion cards requiring communication to devices outside the chassis contain their own card-specific input/output connector located along one edge of the expansion card. This necessitates positioning the expansion cards such that the edge containing the input/output connector is located along the back of the chassis, regardless of whether this is an efficient electrical location on the system planar. With typical computers allowing for a number of expansion boards, the space dedicated to expansion card input/output connectors consume a great deal of area at the back of the computer chassis. Moreover, as has been the case with electronics in general, there has been increased pressure to reduce system planar size with a corresponding pressure to reduce chassis size. The effect has been a steady decrease in the amount of board and chassis space available secure external input/output connectors.
Accordingly, it is desirable to provide for a computer chassis that may be used across a broad range of systems, regardless of the number and type of input/output connectors desired for use in the system, with minimal investment in chassis redesign. Further, it is desirable to place expansion cards in locations that are not adjacent to the system planar edge.